Subject
Outdoor recreation
65
Trails
48
National parks and reserves
41
Roads
29
Shenandoah National Park (Va.)
25
National monuments
17
Historic sites
13
Big Thicket National Preserve (Tex.)
12
Camp sites, facilities, etc
12
Blue Ridge Parkway (N.C. and Va.)
11
Hiking
10
Geology
9
Natural history
9
Recreation areas
9
Grand Canyon National Park (Ariz.)
7
Sand dunes
7
Natural areas
5
Public lands Recreational use
5
Sleeping Bear Dunes National Lakeshore (Mich.)
5
White Sands National Park (N.M.)
5
Chesapeake and Ohio Canal (Md. and Washington, D.C.)
4
Mojave National Preserve (Calif.)
4
Boats and boating
3
Cape Cod National Seashore (Mass.)
3
Catoctin Mountain Park (Md.)
3
Chickasaw National Recreation Area (Okla.)
3
Lake Clark National Park and Preserve (Alaska)
3
Missions, Spanish
3
National Park of American Samoa (American Samoa)
3
Ozark National Scenic Riverways (Mo.)
3
Wild and scenic rivers
3
Battlefields
2
Bicycle trails
2
Bighorn Canyon National Recreation Area (Mont. and Wyo.)
2
Biotic communities
2
Bluestone National Scenic River (W. Va.)
2
Canaveral National Seashore (Fla.)
2
Caves
2
Cumberland Island National Seashore (Ga.)
2
Cunningham Falls State Park (Md.)
2
Cuyahoga Valley National Park (Ohio)
2
Cycling
2
Day hiking
2
Death Valley National Park (Calif. and Nev.)
2
Fugitive slaves History
2
Gauley River National Recreation Area (W. Va.)
2
Glacier Bay (Alaska)
2
Glacier National Park (Mont.)
2
Glen Canyon National Recreation Area (Utah and Ariz.)
2
Grand Teton National Park (Wyo.)
2
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